3D cellulose network confining MXene/MnO2 enables flexible wet spinning microfibers for high-performance fiber-shaped Zn-ion capacitors.

Fiber-shaped Zn-ion capacitors (FSZICs) have shown great potential in wearable electronics due to their long cycle life, high energy density, and good flexibility. Nevertheless, it is still a critical challenge to develop a conductive fiber with long size and high mechanical properties as the FSZIC cathode using sustainable and low-cost materials. Herein, regenerated cellulose (RC) -based conductive microfibers are prepared by a simple, continuous, and scalable wet spinning process. The 3D nanoporous networks of RC caused by physical self-cross-linking allow MXene and MnO2 to be uniformly and firmly embedded. The rapid extrusion and limited drying result in the highly aligned structure of the fibers, endowing the hybrid fiber with an ultra-high tensile strength (145.83 Mpa) and Young's modulus (1672.11 Mpa). MXene/MnO2-RC-based FSZIC demonstrates a high specific capacitance of 110.01 mF cm-3, an energy density of 22.0 mWh cm-3 at 0.57 A cm-3 and excellent cycling stability with 90.5 % capacity retention after 5000 cycles. This work would lead to a great potential of cellulose for application in next-generation green and wearable electronics.

Powering the Future Green Buildings: Multifunctional Ultraviolet-Shielding Transparent Wood.

Indoor UV damage is a serious problem that is often ignored. Common glasses cannot filter UV rays well and have fragility and environmental issues. UV-shielding transparent wood (TW) holds promise, yet striking the right balance between blocking UV rays and allowing sufficient visible-light transmission poses a challenge. The pronounced capillary force, fueled by persistent moisture and extractives in wood, alongside the existence of multiphase interfaces, collectively hinder the uniform penetration of polymers and the effective dispersion of nanomaterials within the wood skeleton. Here, we incorporate high-pressure supercritical CO2 fluid-assisted impregnation (HSCFI) into fabricating UV-shielding TW. The supercritical CO2 pretreatment efficiently eliminates moisture and refines wood structure by extracting polar substances, resulting in a prominent 52.4% increase in average water permeability. Subsequently, this HSCFI method facilitates the infiltration of methyl methacrylate (MMA) monomer and Ce-ZnO nanorods (NRDs) into the refined anhydrous wood, leveraging the excellent solvency of supercritical CO2 for MMA. The impregnation rate of PMMA undergoes a substantial increase from 34.5 to 59.1%. With the robust UV-blocking capability of Ce-ZnO NRDs, thanks to dual-valence Ce doping widening the ZnO energy gap via the Burstein-Moss effect and their unique photoactive microstructure featuring a solid prism with a sharp hexahedral pyramidal tip, along with intrinsic physical scattering/reflection actions, Ce-ZnO NRDs@TW achieves an impressive 99.6% UVA radiation blockage (the highest for TW) and maintains high visible-light transmission (83.2%). Furthermore, Ce-ZnO NRDs@TW presents favorable energy-saving, sound absorption, and antifungal abilities, making it a promising candidate for future green buildings.

A Novel Flame-Retardant, Smoke-Suppressing, and Superhydrophobic Transparent Bamboo.

Silica glass, known for its brittleness, weight, and non-biodegradable nature, faces challenges in finding suitable alternatives. Transparent wood, made by infusing polymers into wood, shows promise but is hindered by limited availability of wood in China and fire risks associated with its use. This study explores the potential of utilizing bamboo, which has a shorter growth cycle, as a valuable resource for developing flame-retardant, smoke-suppressing, and superhydrophobic transparent bamboo. A 3-layered flame-retardant barrier, composed of a top silane layer, an intermediate layer of SiO2 formed through hydrolysis-condensation of Na2SiO3 on the surface, and an inner layer of Na2SiO3, has been confirmed to be effective in reducing heat release, slowing flame spread, and inhibiting the release of combustible volatiles, toxic smoke, and CO. Compared to natural bamboo and other congeneric transparent products, the transparent bamboo displays remarkable superiority, with the majority of parameters being notably lower by an entire order of magnitude. It achieves a long ignition time of 116 s, low total heat release (0.7 MJ/m2), low total smoke production (0.063 m2), and low peak CO concentration (0.008 kg/kg). Moreover, when used as a substrate for perovskite solar cells, the transparent bamboo displays the potential to act as a light management layer, leading to a marked efficiency enhancement of 15.29%. The excellent features of transparent bamboo make it an enticing choice for future advancements in flame-retardant glasses and optical devices.

Research Progress on the Application of Nanocellulose in Glucose Sensing.

BACKGROUND: Nanocellulose is not only a biocompatible and environmentally friendly material but also has excellent mechanical properties, biodegradability, and a large number of hydroxyl groups that have a strong affinity for water. These characteristics have attracted significant attention from researchers in the field of glucose sensing. OBJECTIVE: This review provides a brief overview of the current research status of traditional materials used in glucose sensors. The sensing performance, chemical stability, and environ-mental properties of nanocellulose-based glucose sensors are compared and summarized based on the three sensing methods: electrochemical sensing, colorimetric sensing, and fluo-rescence sensing. The article focuses on recent strategies for glucose sensing using nanocel-lulose as a matrix. The development prospects of nanocellulose-based glucose sensors are also discussed. CONCLUSION: Nanocellulose has outstanding structural characteristics that contribute signifi-cantly to the sensing performance of glucose sensors in different detection modes. However, the preparation process for high-quality nanocellulose is complicated and has a low yield. Furthermore, the sensitivity and selectivity of nanocellulose-based glucose sensors require further improvement.

Constructing N-doped and 3D Hierarchical Porous graphene nanofoam by plasma activation for supercapacitor and Zn ion capacitor.

Traditional electrode materials still face vital challenges of few active sites, low porosity, complex synthesis process, and low specific capacitance. Herein, N-doped and 3D hierarchical porous graphene nanofoam (N-GNF) is created on carbon fibers (CFs) by employing a facile, fast, and environmentally friendly strategy of N2 plasma activation. After an appropriated N2 plasma activation, the graphene nanosheets (GNSs) synthesized by Ar/CH4 plasma deposition transform into N-GNF successfully. N doping donates rich active sites and increases the hydrophilia, while hierarchical nanoarchitecture exposes an enlarged effective contact area at the interface between electrode and electrolyte and affords sufficient space for accommodating more electrolytes. The as-assembled flexible N-GNF@CFs//Zn NSs@CFs Zn ion capacitor delivered a high energy density of 105.2 Wh kg-1 at 378.6 W kg-1 and initial capacity retention of 87.9% at the current of 2 A g-1 after a long cycle of 10,000.